Generic Arguments missing from IdentityUser

[joshmouch]

In Identity 2.0, we had a lot of flexibility in extending the Identity* entities. That flexibility gave us further flexibility in how EF code first migrations interacted with Identity 2.0.

That seems to be completely missing in Identity 3.0.
For one, the following:

IdentityUser<Key, UserLogin, UserRole, UserClaim>

is changed to:

IdentityUser<Key>

This means I can no longer inherit from UserLogin, UserRole, and UserClaim and have the changes get migrated to the database using EF code first migrations.

For example:

public class MyUserRole : IdentityUserRole<Guid>
public class MyUserLogin : IdentityUserLogin<Guid>
public class MyUserClaim : IdentityUserClaim<Guid>
public class MyUser : IdentityUser<Guid, MyUserLogin, MyUserRole, MyUserClaim>
public class MyRole : IdentityRole<Guid, MyUserRole>
public class MyDataContext : DbContext (I set up the Identity entities in this class)

[divega]

@joshmouch thanks for the feedback on this. This change was intentional but I think it is something that we can discuss.

The goal of the change was to not have as many generic arguments leaking into all our types and extension methods. The main disadvantage is that the extensibility scenario you describe now requires replacing the Entity Framework provider with your own code.

cc @rustd @HaoK

[joshmouch]

@divega
As far as I know not having the generic arguments means you can't extend IdentityUserLogin, IdentityUserRole, or UserClaim, because the schema that will get created when EF looks at MyUser : IdentityUser, will have properties of the base types (e.g. IdentityUserLogin rather than MyUserLogin).

I tried for hours to get EF7 to treat MyUser.UserLogins as a type MyUserLogin through the ModuleBuilder.BaseType, but I didn't have any luck. (To get EF to use MyUserLogin for the database schema instead of IdentityUserLogin and to return type MyUserLogin when you reference the property MyUser.UserLogins).

[slaneyrw]

If I could add a voice to this discussion ( also see issue #567 - closed by HaoK ), the current state of the IdentityUser not only lacks extensibility, but it's implementation also couples the Identity* types into UserStore and UserManager and IdentityDbContext.

I'm trying to convert an existing v2 application( in the context of ASP.NET 4 -> 5 ) to access the feasibility.

In order for me to replace IdentityUserClaim I have to replace IdentityUser, IdentityDbContext, then (because UserStore has a generic constraint for TUser on IdentityUser ), replace UserStore as well, finally subclass UserManager to replace ALL the claims functions, working around the useful private/internal functions hidden.

Version 3 is much more closed than version 2 to the point of being a one size fits some / black box.

[joshmouch]

@slaneyrw Thanks for the support! Identity 2.0 definitely made it a design goal to make things one size fits all.

@divega I see you've set 3.0.0.-rc1 as a milestone for fixing this. Can you briefly describe what the public signature portion of the change will be so we can make sure it covers all the bases?

cc @divega @rustd @HaoK

[WiredUK]

I could be wrong, but I don't have a problem with having one or two (or several!) generic versions of the IdentityDbContext class to allow for those people who want to extend the model. I think that can be done pretty cleanly?

[joshmouch]

@WiredUK I'm with you. I think the concern is that many classes get touched. But it still seems clean as it's all "generically typed" touching.

[WiredUK]

@joshmouch I've taken a closer look at the code and it's super easy to extend it. Would a PR to do that be welcome here?

[joshmouch]

@divega @rustd @WiredUK I'm not very familiar with how this github development works in general. It sounds like the team may already be working on it for RC1. I think you'd have to ask them if they would welcome a PR.

[slaneyrw]

This missed RC1, is it going to be targeted for RC2 ?